Flame stabilizing system for power gas burners

ABSTRACT

A power gas burner having a plurality of circumferentially spaced conventional gas jets directed axially of the burner. A conventional flame retention ring surrounds these gas jets. In accordance with this invention, said ring is provided with a plurality of secondary gas nozzles surrounded by an air supply and arranged circumferentially and disposed axially forwardly of the pure gas jets for introducing excess air to stabilize the flame.

[ Feb. 22, 1972 United States Patent Dimick [54] FLAME STABILIZING SYSTEM FOR Primary Examiner-Carroll B. Dority,Jr.

Attorney-Harris Zimmerman POWER GAS BURNERS [72] Inventor:

Enoch Alfred Dlmick, Berkeley, Calif. s. 1. Johnson co., Oakland, cans Nov. 2, 1970 ABSTRACT A power gas burner having a plurality of circumferentially [73] Assignee:

[22] Filed:

spaced conventional gas jets directed axially of the burner. A

[21] Appl. No.: 85,866

conventional flame retention ring surrounds these gas jets, In accordance with this invention, said ring is provided with a plurality of secondary gas nozzles surrounded by an air supply and arranged circumferentially and disposed axially forwardly of the pure gas jets for introducing excess air to stabilize the flame.

ommnfi 42 /532 11 ,4 3 94% 5 3 32 10 6 5 w mm o i o L 4 5 l m w 3 4 A 3 m 9 3 2 [58] fieldofSearch.................

9 Claims, 4 Drawing Figures 43l/284X 3,163,204 l2/l964 lhlenfield...........................431/284X PAIENTEUFEB22 I972 3. 644, 077

sum 1 or 2 FlG 1 .7 INVENTOR.

ENOCH ALFRED DIMICK ATTORNEYS PATENTEDFEB 22 I972 SHEET 2 [1F 2 INVENTOR. ENOCH ALFRED DIMICK AT TORNEYS FLAME STABILIZING SYSTEM FOR POWER GAS BURNERS' BACKGROUND OF THE INVENTION Power gas burners have been in widespread use for many years and are usually connected to a boiler or the like. Conventionally, such burners are provided with a plurality of axially aligned and circumferentially spaced gas jets or nozzles at which the flame is initiated, and the flame front enters the boiler for purpose of generating heat therein. Most of such burners also have means for delivering air for the purpose of properly supporting combustion in the boiler chamber. It will be appreciated, however, that the effectiveness and efficiency of such burners depends on flame stability and if the flame front pulsates, the flame tends to leave the ends of the gas jets, creating further pulsations, vibrations and a generally inefficient operation.

An attempt to overcome this problem, flame retention rings have heretofore been utilized which are intended to spin the main gas supply stream outwardly and into an annular air stream disposed axially forwardly of the gas nozzles. However, this has not solved the pulsation and flame jumping problem.

In accordance with the present invention, a plurality of secondary gas nozzles are provided in an annular pattern axially intermediate the gas supply nozzles and the annular airstream, and each such nozzle is surrounded by an airstream. These secondary nozzles add an initial small amount of air at the start of the flame propagation and serve to keep the gas on the surface of the diffuser ring ignited, thus resulting in a continuous process of ignition in a protected zone and effectively preventing the flame from jumping away from the ends of the main gas supply jets. By maintaining the flame at the main gas jets, the undesirable pulsations are avoided.

THE DRAWINGS FIG. 1 is a longitudinal cross-sectional view of the apparatus of the present invention.

FIG. 2 is a front elevational view of the structure shown in FIG. 1.

FIG. 3 is an enlarged cross-sectional view of the portion of the flame diffuser and retention ring with one of the secondary nozzles.

FIG. 4 is another view, similar to FIG. 3, of another portion of the ring with the ignitor shown therein.

DESCRIPTION The apparatus of the present invention, best shown in FIGS. 1 and 2 of the drawings, includes a generally conventional burner 10, which only for the purpose of explanation, is illustrated as of the combination oil or gas variety. The burner includes a cylindrical housing 12 having an annular flange 14 at its front end for the purpose of mounting the burner on an end wall 16 of a boiler 18 or the like. Housing 12 encompasses an air blower (not shown) as well as the operating burner parts. Mounted within the housing is an annular gas manifold 20 which is connected to a source of ignitable gas through a manifold inlet 22. Extending axially forwardly of the front wall 24 of the manifold are a plurality of main gas jets or nozzles 26, which, as illustrated in FIG. 2, are disposed in a circumferential concentric pattern about the center longitudinal axis of the burner. The ends of the nozzles 26 terminate substantially in the same transaxial plane as the end of an axially extending sleeve 28 which extends forwardly from the manifold and which circumferentially encompasses the nozzles. Sleeve 28 is provided with a plurality of apertures 30 permitting entry of air from a blower to the nozzle tubes 26 intermediate their ends. An inner sleeve 32 extends concentrically from a rear wall 34 of the manifold and terminates rearwardly of the aforesaid transaxial plane. This inner sleeve 32 also receives air from the blower, and when the blower is operating on oil, an oil jet nozzle 36 disposed within sleeve 32 is operated, but when being operated as a gas burner in accordance with the present invention, such nozzle 36 is nonfunctinal.

As above mentioned, it is common practice to provide a power gas burner with a flame retention and diffuser ring, generally indicated at 40. Such ring, as here shown, is supported on and extends axially forwardly and radially outwardly from sleeve 28 in the form of a conical diffuser formed of a plurality of overlapping plates 42 having an airspace between adjacent plates which thus provides a swirling action of the airstreams 44 and 46 entering the same. The forward end of the ring is provided with an annular collar 48, preferably of unperforate design.

Extending forwardly from mounting flange 14 is an annular deflector member 50 whose sidewalls are spaced from ring 40 to define a passage for an airstream 52 to within the boiler 18.

The foregoing construction is generally conventional in the art, and no further or detailed explanation is deemed necessary, except that an aperture may be provided in one of the ring plates 42 through which an ignitor assembly 54 may extend for initially instituting combustion.

In accordance with the present invention, additional gas nozzles 56 in the form of axially disposed tubes 58 are provided in concentric relation about the burner axis. Each tube has its rearward end portion inserted in manifold 20 and its forward end extending just past an aperture 60 provided in each plate 42. It is important to note that the end 56 of each of the tubes which defined a secondary gas nozzle terminates rearwardly of the forward end of ring collar 48. It is also important to point out that apertures 60 are substantially larger than tubes 58, thereby permitting a free flow of air from rearwardly of the ring 40 and through the apertures 60 immediately adjacent the nozzles 56.

The amount of air permitted to pass in the annular space between the tube and aperture produces a relatively lean mixture, and certainly not as rich as the mixture at the main gas nozzles 26.

With the foregoing structure, upon ignition of the main and secondary nozzles a stabilizing flame ring or zone is created on and adjacent the surfaces of the ring plates 42 which keeps the primary gas flowing from the main gas nozzles ignited. There is thus provided a continuous burning from the main nozzles 26, rather than the intermittent and pulsating type of flame when the secondary nozzles and associated air supply is not used.

The main nozzles 26 are preferably larger than the nozzles 56. If the latter are increased in size, there is a tendency for the flame to be smothered at the nozzles 56 and burn a distance away. This would destroy the concept of having a continuous flame zone around the main nozzles to insure continuous ignition. Although the complete theory of the mode of operation is not fully understood, it has been established empirically that when the nozzles 56 are closed, pulsation results, while when open, a smooth flame front results.

I claim:

1. A burner including a plurality of main gas nozzles disposed concentrically in circumferentially spaced relation about the longitudinal axis of the burner, means delivering gas to said nozzles, an annular flame retention member extending forwardly of the discharge ends of said nozzles, means defining a plurality of secondary gas nozzles adjacent the forward end of said member, and means defining air passages for delivering air to adjacent said nozzles.

2. A burner as set forth in claim 1 in which said secondary gas nozzles are operatively connected to said gas delivering means.

3. A burner as set forth in claim 1 in which said gas delivering means includes a gas manifold, and each of said main and secondary nozzles being in flow communication with said manifold.

4. A burner as set forth in claim 1 in which said member includes an outwardly and forwardly diverging portion extending from the ends of said main nozzles and substantially encompassing the same, and said secondary gas nozzles comprising axially disposed tubes extending from said gas delivering means through said diverging portion.

which said latter nozzles are circumferentially spaced about said burner axis on a larger diameter than said main gas nozzles.

8. A burner as set forth in claim 5 in which said diverging portion is formed from a plurality of overlapping plates defining space therebetween for the passage of air therethroughl 9. A burner as set forth in claim 8 in which each of said plates has a tube extending therethrough. 

1. A burner including a plurality of main gas nozzles disposed concentrically in circumferentially spaced relation about the longitudinal axis of the burner, means delivering gas to said nozzles, an annular flame retention member extending forwardly of the discharge ends of said nozzlEs, means defining a plurality of secondary gas nozzles adjacent the forward end of said member, and means defining air passages for delivering air to adjacent said nozzles.
 2. A burner as set forth in claim 1 in which said secondary gas nozzles are operatively connected to said gas delivering means.
 3. A burner as set forth in claim 1 in which said gas delivering means includes a gas manifold, and each of said main and secondary nozzles being in flow communication with said manifold.
 4. A burner as set forth in claim 1 in which said member includes an outwardly and forwardly diverging portion extending from the ends of said main nozzles and substantially encompassing the same, and said secondary gas nozzles comprising axially disposed tubes extending from said gas delivering means through said diverging portion.
 5. A burner as set forth in claim 4 in which said diverging portion is provided with a plurality of axial apertures for receiving the forward ends of said tubes in loose relationship whereby an airflow space is provided between said apertures and the tubes extending therethrough.
 6. A burner as set forth in claim 1 in which said main gas nozzles have a larger discharge diameter than said secondary nozzles.
 7. A burner as set forth in claim 6 in which there are a larger number of main gas nozzles than secondary gas nozzles, and in which said latter nozzles are circumferentially spaced about said burner axis on a larger diameter than said main gas nozzles.
 8. A burner as set forth in claim 5 in which said diverging portion is formed from a plurality of overlapping plates defining space therebetween for the passage of air therethrough.
 9. A burner as set forth in claim 8 in which each of said plates has a tube extending therethrough. 